Shaktipat is the descent of spiritual energy. Since energy is all pervading and is present in every particle of nature, the question arises, "Where does this energy come from and where does it go?"
Shaktipat, thus, means the descent of Chit-Shakti (the power of mind-stuff) of the Guru on the Chit-Shakti of the disciple.
The Guru is regarded to be spiritually more advanced than the disciple. When the higher spiritual power of Guru is transferred to the lower one of the disciple, it arises and activates the disciple's Chit-Shakti and makes it introspective. This awakening and activation is easily possible through Shaktipat.
Kundalini Shaktipat, also known as Kundalini Maha-yoga is a self-perfecting spiritual practice, in which the Kundalini power causes an initiate to perform kriyas (automatic movements) through the power of Kundalini itself. Therefore, its other name is Siddha-yoga, or "the self-proven path of meditation," in which it is the Shakti itself that performs the meditation.
An initiate must not make any effort at all; one's duty is only to surrender. The time and characteristics of the manifestation of Shakti are solely the work of the divine power (Shakti) itself. To practice this type of meditation means that one must simply allow the divine power the opportunity to perform the meditation by itself.